Dai was born as the youngest of three siblings. From her mother, Maki, she had the impression that she was an untouchable child. In the spring of one year, two of her older brothers got a job and lived alone, and her father was assigned to work alone, and her life changed in a hurry, and Dai and Maki began living with two mothers and children. Maki, who felt a sense of loss when the house that was lively suddenly became quiet. Seeing such a mother, Dai felt lonely and frustrated, and tried to regain her mother's love, which she could not monopolize until now.